Ambulatory Diagnostic Device and Method Thereof

ABSTRACT

The present disclosure relates to a device and method for acquiring and processing sensor signals on a host device. The device comprises a jack and connects to a socket on the host device. The device further comprises an instrumentation block which draws power from the host socket to power its operation. The instrumentation block further processes signals and conveys this information to the host device up on connecting the device jack to the host socket. The host device controls certain aspects of the electronics module for acquiring and processing plurality of signals. The instrumentation block in the device connects to one or more sensors through cables to sense at least one of electrocardiogram (ECG), Electroencephalography (EEG), motion, airflow of respiratory system, body temperature, light intensity of arterial oxygen saturation level, blood pressure and any other physiology signal.

TECHNICAL FIELD

The disclosure relates to physiology monitoring devices and moreparticularly relates to an accessory device for sensing and providingphysiological signals to another ambulatory device for monitoring andinterpreting physiology of a person.

BACKGROUND AND PRIOR ART

Recent advances in mobile computing and energy-efficient communicationhave shown promise in the continuous acquisition, storage, andprocessing of physiological signals. Pervasive sensors deployed in nextgeneration networks have enabled algorithms capable of efficient andaccurate information processing. The monitoring of physiology of aperson including, but not limited to electrocardiogram (ECG or EKG)signals and Electroencephalography (EEG) signals may be performed withelectronic devices which are used very regularly by any person.

The monitoring of the ECG signals are performed by interpretation of theelectrical activity of a heart over a period of time, as detected byelectrodes attached to surface of the skin and recorded by a deviceexternal to a body of a person. The recording produced by electricalactivity of heart is termed as an ECG. The monitoring of EEG signals isperformed by recording and interpretation of electrical activity alongthe scalp of a person. The EEG measures voltage fluctuations resultingfrom ionic current flows within the neurons of the brain.

Known in the art are methods for measuring physiological signals of aperson such as breathing, body temperature, oxygen saturation and bloodpressure. For monitoring breathing of a person, a spirometer may beused. A spirometer is an instrument that measures air flow whilebreathing and estimates the air capacity of the lungs, for diagnosingasthma or Chronic Obstructive Pulmonary Disease (COPD). The bodytemperature is an important indication of health including fever,sepsis, heat rash, or any other disease which may affect the persons.Measurement of temperature may be carried out using an electronic devicewith an Infra Red (IR) sensor.

Pulse oximeters may be used to monitor Oxygen saturation in a person,which is measurement of concentration of oxygen in arterial bloodreaching tissues. The peripheral oxygen satuaration (SpO2) can bemeasured non-invasively by using a pulse oximeter. A pulse oximeterdevice comprises a photodetector that responds to red and infra-redlight through tissue, such as finger tip, ear lobe, etc. and thenprocesses the signal to estimate SpO2. Arterial Blood Pressure (BP) isanother physiological signal that can be estimated non-invasively, usingmany techniques including the oscillometric principle. The amplitude ofpressure change in a cuff on the upper arm of a person, which isinflated and then deflated, is sensed by a pressure sensor. The sensedsignal is processed to estimate systolic and dialostic BP. For measuringany physiological parameter, plurality of sensors are used to sense somespecific aspect of underlying physiology. The sensed signals are thenprocessed using software algorithms running on special purpose medicaldevices, general purpose computers, micrprocessors, ASICs, or any othercomputing device.

Recently, cellphones, smartphones, tablets and other personal deviceshave become ubiquitous. These devices along with laptops and desktopcomputers are herein after referred as a Host device. Most of the hostdevices provide a headphones socket that provides audio signal to theear buds. Also, they provide power to microphone and receive the signalfrom the microphone. Headphones that incorporate microphones fortelecommunications are typically called headsets. Hereinafter in thisdescription, the terms headphone and headset are used interchangeably. Aheadphone jack and a headphone socket require a physical, electricalconnection to interoperate. Hereinafter in this description, the termsjack and socket are used to represent any electrical connection. Thewiring for headphones and headsets using typical 3.5 mm, 4 pin jacks andcompatible sockets is known as TRRS (tip, ring, ring, and sleeve)configuration as shown below.

Pin Number Pin Name Description 1 Tip Left Audio Out 2 Ring 1 RightAudio Out 3 Ring 2 Common/Ground 4 Sleeve Microphone Input

Known in the art is a headphone or electret microphones cable with aheadphone jack on one side, which may be interfaced with the Hostdevice. The headphones commonly used in hands free, voice callapplications require microphone-bias to power a preamplifier that isinternal to the microphone assembly. The socket on a host device ormobile device or consumer device provides the bias on the Microphoneinput (pin-4) and Common/Ground (pin-3), while receiving the audiosignal from the microphone on the same two pins. The essential point isthat power to a sensor and signal communication from the sensor isaccomplished on a two-wire interface. A limitation of this AC-coupledarchitecture is that the input signals can only be AC signals, withouthaving any information in the lower frequencies of the input signalssuch as audio and speech.

FIG. 1 shows a typical microphone connection to headphone socket onSmartphones and Tablets. The junction gate field-effect transistor(JFET) provides amplification and impedance matching. The resistor Rvalues are in the rage of 1-10 KΩ which provides the required biasvoltage and sources current for JFET operation. Also, the capacitor Cvalues are in the range of 1-50 μF and blocks DC voltage while passingaudio signals for ADC. The microphone becomes a current source,delivering few hundred μA. Thus, the two-wire interface can providepower to the sensor and also receive the analog data from the sensorusing ac-coupled interface.

FIG. 2 shows a conventional ECG Equivalent Circuit. The impedance of thecircuit of FIG. 2 for the commonly used electrodes is shown in FIG. 3.The impedance can be sometimes as high as 500 kΩ. This variability isdue to the variation in off the shelf Ag/AgCl electrodes and due toaging in disposable electrodes. The ECG signals have a bandwidth in therange of 0.05 to 100 Hz. Typical amplitude of ECG signals is about 5 mV.The signals can sometimes ride on a DC bias of ±300 mV. There issignificant diagnostic information in the lower frequencies that wouldbe filtered by the high pass filtering action at the audio socket insmartphones. The reusable sintered Ag/AgCl electrodes mitigate theelectrode variability to a large extent. Similarly, for signals such asair flow, temperature, light intensity, and pressure which correspond tocertain physiological aspects of interest to clinicians, the frequencycontent is well below that of speech and audio. As the capacitor C inFIG. 1, will block low frequency signals, such a socket is not usefulfor receiving physiological signals.

In a patent application US 20130331663 discloses heart monitoring systemusable with a smartphone or computer. It discloses a personal monitoringsystem with a sensor assembly to sense physiological signals. The systemrequires frequency modulated (FM) physiological audio signal andrequires a carrier frequency to be in the range of 6-20 kHz. Here, theFM signal is an audio signal and is not an electric signal. Also, theaudio transmitter of the personal monitoring system transmits an audiosignal to the microphone.

A U.S. Pat. No. 8,509,882 discloses a personal monitoring device usablewith a smartphone or computer. The device uses a frequency modulation(FM) demodulation and generates acoustic signal. The carrier signal isin the range of 6-20 kHz. The device uses an in-built microphone and anaudio isolation transformer to interface to smartphone or a computer.

Typically, for headphones, powering the microphone sensor usingmicrophone bias provided by the electronic device is known. Themicrophone sensor is limited to sensing speech, audio and ambient soundsignals. The audio jack interface of the electronic device is not usedfor ECG, EEG and other physiological signals. Systems for poweringdevices connected to the audio jack and provide digital communicationwith the phone are known in the art. In these systems, the phonegenerates an audio signal that is rectified and filtered to generatepower for an external device. The microphone port is reserved forcommunicating discrete data from the device to the phone. The microphonebias is not used to power external devices.

Accordingly, a need exists for a device and method for monitoringphysiological signals using cellphones, smartphones, tablets and otherpersonal devices.

SUMMARY

The shortcomings of the prior art are overcome and additional advantagesare provided through the provision of a method and system as describedin the description.

One embodiment of the present disclosure is a first device also referredas a smart accessory or a smart cable. The first device is having atleast one instrumentation block and a jack connectable to a seconddevice with a socket and at least one sensor. The first devicecomprising at least one amplifier in the instrumentation blockconfigured to amplify at least one signal received from the at least onesensor and one or more modulators in the instrumentation block. The oneor more modulators are configured to modulate at least one amplifiedsignal. The at least one modulated signal is transmitted to the seconddevice upon connecting the jack to the socket. The analog signal fromthe first device is referred to as “composite analog signal”. The signaltransmitted from the first device is understood to be composite analogsignal, even if not explicitly stated for brevity. Also, the firstdevice is configured to receive power from the second device uponconnecting the jack to the socket. The at least one signal is one ofelectrocardiogram (ECG), Electroencephalography (EEG), motion, airflowof respiratory system, body temperature, light intensity of arterialoxygen saturation level, blood pressure and any other physiology signal.

Another embodiment of the present disclosure is a second device alsoreferred as host device having at least one ADC, at least one controlunit, at least one modem and at least one socket connectable to a firstdevice with at least one instrumentation block and a jack. The seconddevice comprising the at least one ADC configured to receive an analogsignal from the first device through the at least one socket uponconnecting to the jack and convert the analog signal in to a digitalsignal. The analog signal received by the second device is understood tobe composite analog signal, even if not explicitly stated for brevity.The control unit configured to receive the digital signal and performband pass filtering, demodulation and extracting features from at leastone raw signal sensed by the first device.

Yet another embodiment of the present disclosure is a first device withat least one sensor, at least one actuator, an instrumentation block anda jack connectable to a second device with a socket. The first devicecomprises at least one amplifier in the instrumentation block configuredto amplify at least one signal received from at the least one sensor.Also, the first device comprises at least one driver unit in theinstrumentation block to actuate at least one actuator, wherein the atleast one driver receives a driver signal from the second device uponconnecting the jack to the socket. The at least one composite analogsignal sensed by the at least one sensor is transmitted to the seconddevice upon connecting the jack to the socket.

Another embodiment of the present disclosure is a second device with atleast one ADC, at least one DAC, at least one control unit, at least onemodem and at least one socket connectable to a first device with atleast one instrumentation block and a jack. The second device comprisesthe at least one ADC configured to receive a composite analog signalfrom the first device through the at least one socket upon connecting tothe jack and convert the analog signal in to a digital signal. The atleast one control unit is configured to provide at least one actuationsignal to the at least one DAC, receive at least one digital signal fromthe at least one ADC and process the at least one digital signalreceived from the at least one ADC. The at least one drive signal istransmitted from the at least one DAC to the first device uponconnecting the at least one socket to the jack.

Another embodiment of the present disclosure is a method for processingat least one signal being sensed by at least one sensor using a firstdevice. The method comprising receiving the at least one signal beingsensed by the at least one sensor, amplifying the received at least onesignal, performing a predefined modulation on the amplified at least onesignal and transmitting the composite signal with at least one modulatedsignal to a second device through a jack of the first device, uponconnecting the jack to at least one socket of the second device.

Yet another embodiment of the present disclosure is a system to acquireand process at least one signal from at least one sensor. The systemcomprises a first device with at least one instrumentation block and ajack connectable to a second device with a socket and the at least onesensor. The first device comprises at least one amplifier in theinstrumentation block configured to amplify at least one signal receivedfrom the at least one sensor and one or more modulators in theinstrumentation block, wherein each of the one or more modulatorsconfigured to modulate at least one amplified signal, the compositesignal with at least one modulated amplified signal is transmitted tothe second device upon connecting the jack to the socket. The systemalso comprises a second device with at least one ADC, at least onecontrol unit, at least one modem and at least one socket connectable tothe first device. The second device comprising the ADC configured toreceive the composite signal with at least one modulated amplifiedsignal from the first device through the at least one socket uponconnecting to the jack and convert the modulated amplified signal in toa digital signal and the control unit configured to receive the digitalsignal and perform band pass filtering, demodulation and extracting atleast one raw signal sensed by the at least one sensor.

Another embodiment of the present disclosure is a method for processingsensor signals. The method comprises receiving one or more signalssensed by one or more sensors, amplifying the received one or moresensed signals, performing a predefined modulation on the one or moreamplified signals, combining the one or more modulated signals to form acomposite analog signal, and transmitting the composite signal to a hostdevice for further processing.

Yet another embodiment of the present disclosure is a method foracquiring and processing a composite signal on a second device. Themethod comprises receiving a composite signal, converting to digitaldomain, separating one or more signals from the composite signal,demodulating the separated one or more signals to base band, extractingone or more features from the base band signal and optionallycommunicating the one or more base band signals and the extractedfeatures.

Yet another embodiment of the present disclosure is a third device,which is also a host device, comprising at least one control unit, atleast one modem, and at least one Graphical User Interface unit. The atleast one control unit is configured to receive at least one digitalsignal corresponding to the composite analog signal generated by a firstdevice and perform at least one of band pass filtering, demodulation andextracting at least one raw signal sensed by a first device. The thirddevice further comprises one or more band pass filters to perform bandpass filtering.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF DRAWINGS

The novel features and characteristics of the disclosure are set forthin the appended claims. The embodiments of the disclosure itself,however, as well as a preferred mode of use, further objectives andadvantages thereof, will best be understood by reference to thefollowing detailed description of an illustrative embodiment when readin conjunction with the accompanying drawings. One or more embodimentsare now described, by way of example only, with reference to theaccompanying drawings in which:

FIG. 1 shows a schematic diagram of a microphone jack and headphonesocket, in accordance with a prior art embodiment;

FIG. 2 shows an equivalent circuit for a biopotential sensor, inaccordance with a prior art embodiment;

FIG. 3 shows a plot illustrating magnitude of impedance as function offrequency for typical biopotential electrodes, in accordance with aprior art embodiment;

FIG. 4 shows a smart accessory or a smartcable device for acquiring ECGsignals on host devices, in accordance with an embodiment of the presentdisclosure;

FIG. 5A shows a block diagram of the electronic module orinstrumentation unit of a smartcable, according to an embodiment of thepresent disclosure;

FIG. 5B shows a conventional modulator circuit;

FIG. 6A shows an airflow sensor based on venturi principle with3-Terminal interface, according to known art;

FIG. 6B shows smart accessory for acquiring breathing signals on hostdevices, according to another embodiment of the present disclosure;

FIG. 7A shows a block diagram of an electronic module of the smartaccessory or smartcable, according to an embodiment of the presentdisclosure;

FIG. 7B shows a block diagram of an electronic module of the smartaccessory, according to another embodiment of the present disclosure;

FIG. 7C shows a block diagram of an electronic module of the smartaccessory without low-dropout regulator, according to yet anotherembodiment of the present disclosure;

FIG. 8 shows an illustration of monitoring oxygen saturation using pulseoximeter smartcable, according to an embodiment of the presentdisclosure;

FIG. 9 shows a smart accessory or smartcable for multiple physiologicalparameters according to an alternative embodiment of the presentdisclosure;

FIG. 10 shows a block diagram of a host device, according to anembodiment of the present disclosure; and

FIG. 11 shows a Signal and Feature extraction Module of the host sidefor ECG, EEG, motion, airflow, temperature, light intensity, pressureand other signals, in accordance with an embodiment of the presentdisclosure.

The drawings for the sake of uniformity depict embodiments of thedisclosure for purposes of illustration only. One skilled in the artwill readily recognize from the following description that alternativeembodiments of the structures and methods illustrated herein may beemployed without departing from the principles of the disclosuredescribed herein.

DETAILED DESCRIPTION

In the present document, the word “exemplary” is used herein to mean“serving as an example, instance, or illustration.” Any embodiment orimplementation of the present subject matter described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiment thereof has been shown by way ofexample in the drawings and will be described in detail below. It shouldbe understood, however that it is not intended to limit the disclosureto the particular forms disclosed, but on the contrary, the disclosureis to cover all modifications, equivalents, and alternatives fallingwithin the spirit and the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof,are intended to cover a non-exclusive inclusion, such that a setup,device or method that comprises a list of components or steps does notinclude only those components or steps but may include other componentsor steps not expressly listed or inherent to such setup or device ormethod. In other words, one or more elements in a system or apparatusproceeded by “comprises . . . a” does not, without more constraints,preclude the existence of other elements or additional elements in thesystem or apparatus.

The present disclosure discloses acquiring and processing physiologicalsignals through one or more sensors. The physiological signals include,but are not limited to, Electrocardiography (ECG),Electroencephalography (EEG), motion, airflow of respiratory system,body temperature, arterial oxygen saturation level, and blood pressure,collectively called “Signals” on handheld devices or computing devicessuch as but not limited to smartphones, tablets, Personal Computers(PCs), etc., collectively called “Host device” or a second device or athird device, using a smart accessory or smartcable or a first device.

One embodiment of the present disclosure is a device also referred to asa first device or smart accessory or a smartcable comprising a jack forconnecting the first device to a host device, also referred to as asecond device through a socket. Also, the first device comprises aninstrumentation block connected with a jack on one side and one or moresensor cables on the other side, wherein the instrumentation blockreceives predefined signals being sensed by one or more sensors throughthe one or more sensor cables. The instrumentation block comprises anamplifier to amplify the sensed signals being received from one or moresensors. The amplifier is an instrumentation amplifier. Also, theinstrumentation block comprises one or more modulators to perform apredefined modulation on the amplified sensed signals being receivedfrom the amplifier. The modulation includes, but not limited toamplitude modulation (AM), phase modulation (PM), frequency modulation(FM), etc. In one embodiment, the predefined modulation is FM and themodulator is a Voltage Controlled Oscillator (VCO). The modulationretains low frequency contents of the amplified sensed signals forfurther processing. The instrumentation block may comprise a primaryand/or a secondary cell for powering the instrument block. Further, theinstrumentation block may comprise a regulator to provide predeterminedpower to the amplifier and the modulator, where said regulator receivespower through a jack from a socket of the host device that thesmartcable connects to. The modulated signals from the modulator aretransmitted as a composite analog signal to the second device forprocessing through the jack of the first device. The signals beingsensed by the one or more sensors are one of ECG, EEG, motion, airflowof respiratory system, body temperature, light intensity changes due toarterial oxygen saturation levels, blood pressure and any otherphysiological signals.

An exemplary embodiment of the present disclosure is a cable alsoreferred as smartcable or smart accessory or first device 401, which isshown in FIG. 4. The first device 401 comprises a jack 407 forconnection to a host device, referred as a second device 402. TheElectronics module or instrumentation block 403 is embedded in the firstdevice 401 and draws power from a headphone socket, referred as a socket408 to power its operation. The Electronics module 403 further processessignals such as, but not limited to, Electrocardiography (ECG),Electroencephalography (EEG), motion, airflow, temperature, lightintensity, pressure, and transmits this information as a compositeanalog signal to the Host device or the second device 402 via the jack407 and the socket 408. The Host device 402 may additionally controlcertain aspects of the electronics module 403 for acquiring andprocessing plurality of signals. In an exemplary embodiment, theelectronics module 403 in the first device connects to one or moretransducers/sensors, such as ECG electrodes, collectively referred by anumber 404 as shown in FIG. 4 and through cables Cable-1, Cable-2,Cable-i and Cable-n collectively referred by a number 405, as shown inFIG. 4. The transducers at the other end of these cables may include asintered Ag/AgCl electrode 404 each, embedded in a comfortableankle/wrist fastener. The sintered Ag/AgCl electrodes 404 providesuperior performance for sensing bio potential signals such as EEG andECG signals. The transducers may include but not limited to othersensors, such as pressure, temperature, motion, airflow, temperature,light intensity, pressure, etc., connected to Cable-1 through Cable-n(these transducers are not shown in FIG. 4).

In one embodiment, the Host device or the second device 402 comprises aninternal Analog-to-Digital Convertor (ADC) 409, a central processingunit (CPU) or referred to as a control unit or a controller 410, memory(not shown in the figure) and a modem 411 to transmit information on anynetwork (not shown in figure), as depicted in FIG. 10. The ADC 409converts the composite analog signal received from the first device 401though the socket 408 in to discrete domain. The Host device 402 CPU 410processes the discrete domain information to extract at least onesignal, such as ECG, EEG, motion, airflow, temperature, light intensity,pressure, and any other physiology signals. The Host device 402 maydeduce additional information such as, but not limited to theinformation relevant for convalescence, health monitoring, fitness,endurance training, etc. from the plurality of extracted raw signals.The Host device 402 may communicate at least one of extracted signalsand the deduced information through the modem 411 via wired or wirelesscommunication to another device also referred to as third device such asbut not limited to, clinician devices, coach devices. The Host device402 may also communicate said information to any network or the Internetvia access points, gateways, etc. In one embodiment, the Host device 402may digitize the composite analog signal and transmit it to a thirddevice for further processing.

As shown in FIG. 4, the transducers/sensors which sense the signalsinclude, but are not limited to, ECG and EEG, motion, airflow,temperature, light intensity, pressure, and any other physiology signalswhich have very low frequency content that are clinically relevant. Theheadphone socket 408 of a typical Host device 402 is AC coupled, sincethere is no audio information below 20 Hz. Theinstrumentation/electronics module 403 pre-conditions the signal andperforms frequency modulation (FM) to the audio band in the range of,for example, 20-20000 Hz. For a first device or smart accessory or asmartcable 401 supporting plurality of sensors 404A, 404B, etc. as shownin FIG. 9, each sensor signal is modulated to a different centerfrequency, thus enabling a pair of wires connected to Pin 4 505 and Pin3 504 to carry a plurality of sensor signals. The modulation may be FM,although other types of analog modulation techniques such as AM, PM,etc. that shift the spectrum of the sensor signal are also possible. Thepresent disclosure enables mobile devices such as, but not limited to,smart phones and tablets which are becoming ubiquitous to acquire andprocess the ECG, EEG, motion, airflow, temperature, light intensity,pressure, and other sensor signals using a smartcable system, thusextending their use as ambulatory diagnostic instruments. The batteryand processing power of the Host device 402 is leveraged to lower thecost, while providing superior signal quality commensurate withdiagnostic instruments used inside hospital walls.

In one embodiment, the first device 401 may obtain sensor signals fromsensors incorporated in other wearable devices such as, but not limitedto vests and helmets that provide adequate real estate to house ADC,processing and transmission, including a battery to power theelectronics. However, the number of wires or cables 405 required toconnect all the sensors 404 to the electronics module 403 may beprohibitive from space, reliability and cost perspectives. As anexample, in one embodiment, EEG caps may include electrodes in the rangeof 64 to 256. Also, there may be motion related signals generated by thesensors that provide additional information. In one embodiment, thevests may comprise few tens of ECG's and other sensors. In suchapplications, a two wire system may be used to carry a composite analogsignal multiple sensor signals, wherein each sensor signal is modulatedto a different center frequency. The wearable system can use much higherspectrum than the audio band of 20 to 20,000 Hz, since the compositeanalog signal will interface to an ADC that is not limited by the audioband headphone interface. In one embodiment, such a wearable system mayuse separate lines for powering the electronics and a two-wire interfacefor the signal plane to communicate the composite analog signal to theelectronics module. In another embodiment, such a wearable system mayincorporate a primary or a secondary cell to power the electronics inthe said first device.

FIG. 5A shows a block diagram 400 of the system including the electronicmodule or instrumentation unit 403 of a smartcable or a first device401, and block diagram of a second device 402 in accordance with anembodiment of the present disclosure. As shown in the FIG. 5A, theinstrumentation unit 403 comprises an instrumentation amplifier (IA)501, at least one low dropout regulator (LDO) 503 and one or moremodulators or modulator circuits or voltage controlled oscillators (VCO)502. The IA 501 receives signals from one or more sensors/transducersthrough one or more cables. The signals may include, but not limited toECG, EEG, airflow, temperature, light intensity, pressure and motionsignals. The differential signal from two cables (or one ECG Lead),connected to two sensors/transducers is converted to a single-endedsignal and amplified by the IA. In one embodiment, there may be multipleIA's 501 in an electronic module 403 of a first device 401. To preservelow frequency information in the signal, a frequency modulation is usedto heterodyne the signal to audio band using the VCO 502. The IA 501 andthe VCO 502 are powered using the microphone-bias from Pin 4 505. Acapacitor (not shown in FIG. 5A) may be placed in close proximity to thepower supply pins of the IA 501 and the VCO 502 to improve Power SupplyRejection Ration (PSRR). Alternately, a Low-dropout (LDO) regulator 503can be used to provide stable power to the first device 401 electronicsassembly.

The second device or host device 402 comprises an ADC 409 to digitizethe composite analog signal from the first device 401 in to a compositediscrete signal. Further, the second device 402 comprises a processorwith a bandpass filter for filtering the composite discrete signal toextract at least one modulated signal. Further, the second device maycomprise a software or a demodulation module 410 to extract raw basebandsignals such as, but not limited to, ECG, EEG, motion, airflow,temperature, light intensity, pressure, and other physiological signalsfrom the said discrete signals. A very high FM bandwidth, for exampleabout 5-6 kHz, centered around 5-10 kHz, may be used to provide a highresolution signal after demodulation. This will result in a very lowInput Referred Noise (IRN), for example less than 10 μV, afterdemodulation. An IRN of less than 10 μV is typically specified forhigh-end ECG monitoring instruments used during cardiac procedures inhospitals. The FM bandwidth may be different for other signals such asmotion, airflow, temperature, light intensity, pressure, etc., dependingon the maximum frequency (i.e. ½ Nyquist frequency) of the said signal.

One embodiment of the present disclosure is an ECG Sensor Interface. Thenotations RA, LA, LL and RL are normally used to represent electrodesplaced on the subject's Right Arm, Left Arm, Left Leg and Right Leg,respectively. An ECG lead/cable is the differential signal providedbetween two electrodes. The ECG limb leads are the differential signalsbetween two ECG electrodes placed on the subject's limbs. Lead Icorresponds to LA-RA, Lead II corresponds to LL-RA and Lead IIIcorresponds to LL-LA. The electrode placed on the right leg (RL) is usedto place a modified version of the sensed signals back on the patient,in order to reduce the effects of power line interference and improveCommon Mode Rejection Ratio (CMRR). This approach is called Right LegDrive (RLD). The RLD is very useful in ECG systems powered from mainlines.

In one embodiment of the present disclosure, an InstrumentationAmplifier (IA) 501 of a first device 401 is capable of acquiring anysensed signals such as, but not limited to ECG signals from limb leads.As shown in FIG. 5A, a differential input interface is provided to theIA 501. For example, the IA 501 used may be IC AD8232. The AD8232provides for many ECG sensing functions in an integrated circuit,reducing the need for multiple discrete components.

The one or more Modulators or Voltage Controlled Oscillator (VCO) 502 ofthe electronic module 403 as shown in FIG. 5A may be realized usingmultiple configurations for operation in the audio band. The VCO 502 ofthe electronic module 403 functions as a frequency modulator. An exampleof a VCO is a Wein Bridge Oscillator. In another example, the VCO 502 isa varactor diode VD₁ shown in FIG. 5B. The FIG. 5B illustrates anexample modulator circuit of the many modulation circuits known in theart. The output of the IA 501 drives the modulating input of the VCO 502shown in FIG. 5B. The Vcc line 510 as shown in FIG. 5B is same as Vddline 507 in the FIG. 5A.

Electrophysiological signals or bio-potential signals such as EEG andEEG may be sensed using electrodes but for parameters such as, but notlimited to, motion, airflow, temperature, light intensity and pressure,they are first converted in to electrical signals using an appropriatesensors.

An airflow sensor using a venturi tube 600 with 3-Terminal interface isshown in FIG. 6A. The constriction in the venturi tube 600 creates adifferential pressure between P1 603 and P2 604 shown in FIG. 6A. Asilicon differential pressure sensor 602 converts the pressuredifference due to airflow in the veturi tube in to an electrical signal.The differential pressure sensor comprises a three wire interfaceconsisting of ground 607, power supply Vdd 605 and signal V 606. Thesignal V 606 is a spirometry signal which has amplitudes that correspondto breathing volumes and frequency corresponding to the breathing rate.The venturi tube 600 is shown as an example and other transducers forsensing airflow are known in the art. The spirometry signal includesboth positive and negative swings corresponding to exhalation andinhalation; however the frequency content is very low.

In one embodiment of the present disclosure, the sensor may be anairflow sensor, provisioned in a first device connected to a seconddevice for performing pulmonary finction tests (PFTs) and for measuringphysiological parameters of lung function. In order to preserve the lowfrequency information in the spirometry signal, a frequency modulationtechnique is used to heterodyne the spirometry signal to audio bandusing modulator circuit or voltage controlled oscillator (VCO), which isin the electronics module 608, as shown in FIG. 6B. FIG. 7A shows ablock diagram of the electronic module or instrumentation unit of thefirst device, in accordance with an embodiment of the presentdisclosure. As shown in FIG. 7A, the IA 501 and the VCO 502 are poweredusing a microphone-bias from a Pin 4 505 from the second device uponconnecting jack of the first device to a socket of the second device. Inone embodiment, the sensor 404 and the electronics 403 may beincorporated in breathing tube 600 equipped with a jack 407 (not shownin the figure) for plugging in to socket of a second device. In anotherembodiment, the first device or the smartcable may be of negligiblelength, so that the jack 407 is mounted on the breathing tube 600, asshown in FIG. 6B. In another embodiment of the present disclosure is aprimary cell or a secondary cell (figure not shown) may be used in thefirst device to power to the sensor 404, amplifier 501 and the modulatoror VCO 502.

In one example embodiment of the present disclosure, the sensor as shownin FIG. 7A is a Gauge pressure sensor. The gauge pressure sensorcomprises one port (not shown in the figure) to measure pressurerelative to the atmospheric pressure. The gauge pressure sensor and theassociated electronics may be incorporated in an inflatable compressioncuff placed on a user's upper arm and a cable with a jack for pluggingin to a host device socket (figure not shown). When the cuff is inflatedabove the systolic pressure and the cuff is deflated, the output signalof the gauge pressue sensor reflects systolic blood pressure (BP),diastolic BP and the Mean Arterial Pressure (MAP). Processing of thepressure sensor signal is performed by oscillometric principles toobtain systolic BP, diastolic BP and MAP values.

The gauge pressure sensor comprises a three wire interface consisting ofground, power supply Vdd and the signal V. The signal V may be referredas oscillometric signal having a frequency components related to heartrate, as the pulsatile flow of blood affects the sensor signal duringdeflation. In order to preserve the low frequency information in theoscillometric signal, a frequency modulation is used to heterodyne theoscillometric signal to audio band using the VCO, as shown in FIG. 7A.The IA and the VCO are powered using the microphone-bias from Pin 4. Thehost device performs demodulation and extracts the systolic BP,diastolic BP and mean arterial pressure (MAP) values. In anotherembodiment of the present disclosure a primary cell or a secondary cell(figure not shown) may be used in the smart accessory to power to thesensor, amplifier and the modulator.

In an example embodiment of the present disclosure, the sensor 404 asshown in FIG. 7A may be a thermopile, infra red (IR) sensor to sensetemperature. The IR sensor incorporates thermopiles to detecttemperature and a thermal resistor or thermistor that changes resistancebased on the detected temperature. The IA 501 converts the resistancechanges due to thermistor in to a voltage changes. The VCO 502, shown inFIG. 7A generates a frequency in the audio range corresponding to thetemperature. The sensor 404 and the electronics 403 may be incorporatedin small module with an ear probe and a jack for plugging in to a seconddevice socket (figure not shown). The second device receives signal fromsensor 404 up on connection and performs demodulation to estimate thetemperature.

FIG. 7B shows an electronic module 403 of a first device configured toreceive a carrier signal generated at a second device 402, forperforming frequency modulation, in accordance with an embodiment of thepresent disclosure. The carrier frequency signal for the VCO 502 isgenerated using internal application on the processor and delivered tothe first device on either Pin 1 (Audio Left) or Pin 2 (Audio Right)702. This way of generating frequency carrier signal provides additionalbenefit of providing a stable reference during the demodulation processin the second device. In addition, this generation of frequency carriersignal reduces the cost and size of the electronics module 403 embeddedin the first device, which is as shown in FIG. 7B.

In one embodiment, an electronic module of the first device or the smartaccessory or the smartcable without use of low dropout regulator isshown in FIG. 7C. An instrumentation amplifier (IA) 501 receives signalsfrom one or more sensors/transducers 404 through one or more cables ofthe first device. The sensors 404, 602, 803 may include, but not limitedto ECG, EEG, airflow, temperature, light intensity, pressure and motionsignals. The differential signal from two cables (or one ECG Lead),connected to two sensors/transducers is converted to a single-endedsignal and amplified by the IA 501. The IA 501 and the VCO 502 arepowered using the microphone-bias from a Pin 4 403. A capacitor (notshown in FIG. 5) may be placed in close proximity to the power supplypins of the IA 501 and the VCO 502 to improve Power Supply RejectionRation (PSRR).

One embodiment of the present disclosure is a first device or asmartcable connected to a second device or a host device for measuringperipheral arterial oxygen saturation (SpO2). A pulse oximeter is usedto measure arterial oxygen saturation in peripheral tissues. The pulseoximeter comprises a plurality of light emitting diodes (LED) and aphotodetector. The photodetector converts received light from said LEDsto a corresponding voltage. The LEDs emit light at specific wavelengthswhen excited and elicit a response from the photodector.

FIG. 8 shows an illustration of monitoring oxygen saturation using pulseoximeter according to an embodiment of the present disclosure. As shownin FIG. 8, when a light source via plurality of LEDs (804A and 804B,collectively referred as 804) and a photodector 803 are placed on one ofa finger, ear lobe or any other similar body part that is adequatelyperfused, the response of the photodector depends on the pulsatile bloodflow. The light source using a red LED drive 808 and an IR LD drive 807illuminates the Red LED 804B and the Infra Red LED 804A respectively, inan alternating fashion to elicit response of the photodector 803 to redand infrared light. A second device or a host device generates IR andRed LED excitation signals using an IR LED excitation block 822 and ared LED excitation block 823 respectively.

As shown in FIG. 8, the excitation of LEDs includes regions to enablephotodetector 803 in sensing red light, IR light and ambient light. Alow pass filtering effect is observed on the signals as they go througha digital to analog converter (DAC) 819 and analog interface through Pin1 814, 809 and Pin 2 815, 810 to the IR LED drive 807 and red LED drive808 respectively. The IR 807 and red LED drives 808 provide necessarybias and current to drive the LEDs 804. In one embodiment, the drivesinclude diodes (not shown in the figure) to restore the square pulseshapes for accurate timing of actuating signals and capacitors to storeadequate charge to elicit optimal response from the photodetector 803.Each of the LEDs 804 is driven around 16000 times a second, althoughother values are possible depending on the drive circuits used. As shownin FIG. 8, the instrumentation amplifier (IA) 805 receives power fromLow dropout regulator (LDO) for performing signal conditioning.

In one embodiment a VCO may not be required, as the frequency of theinformation at Pin 4 is already in the audio band. At the second deviceor the host device, the digitised data is band pass filtered using aband pass filter 818 to eliminate noise. The filtered data is re-sampledin synchronization with excitation signals by the Excitation SynchronousSampling module 820 to generate samples during red LED activation, IRLED activation and ambient conditions, which are received by IR samplesunit 825, red samples unit 825 and ambient samples unit 827respectively. In one embodiment, a delay alignment module 821 maycompensate for any delays due to the latencies related to the audiointerface, drive circuits, and the band pass filter (BPF). In oneembodiment, the delay alignment module 821 may receive timinginformation from the IR LED Excitation module 822 and the Red LEDExcitation module 823.

FIG. 9 shows a first device or a smartcable with multiple sensors, inaccordance with an embodiment of the present disclosure. FIG. 9 showstwo ECG signals 404A, 404B as an example. The audio bandwidth supportedby a headset socket and an analog to digital converter (ADC) of a seconddevice is much greater than that required for frequency modulated ECG,even with the large FM bandwidth of 5-6 kHz. This allows the firstdevice to support more than one ECG lead with proper allocation ofchannels and using Frequency Division Multiple Access (FDMA). As anexample, the first device may support a 3-Lead ECG by using twoinstrumentation amplifiers 501A, 501B, two modulators or voltagecontrolled oscillators and a summer or an adder 901 using an op-amp, asshown in FIG. 9. The second device processor 410 implements multipleband pass filters to separate channels and demodulate each ECG channel.

As shown in FIG. 9, for the first device or the smartcable it ispossible to acquire plurality of limb leads (I, II and III) using two FMchannels, since any two limb leads can be combined to derive the thirdlead as shown below:

Lead I=LA−RA=Lead II−Lead III

Lead II=LL−RA=Lead III+Lead I

Lead III=LL−LA=Lead II−Lead I

Also, the embodiment as shown in FIG. 9 may monitor fetal ECG, alongwith mother's ECG. The two electrodes for fetal ECG will use awaistband, instead of two wrist/ankle fasteners. This is not shown inFIG. 9, but one skilled in the art will readily recognize that multiplesensors, including but not limited to ECG, EEG, motion, airflow,temperature, light intensity, pressure and other physiological signalscan be sensed by a plurality of IA and VCO modules in the first deviceand communicated to the second device or Host device as a compositeanalog signal. The ADC 409 in the Host device receives the compositesignal, with plurality of signals frequency modulated at differentcenter frequencies. The ADC 409 converts this analog data in tocomposite discrete FM stream, comprising one or more of ECG, EEG,motion, airflow, body temperature, light intensity changes due toarterial oxygen saturation level, blood pressure and other physiologicalsignals.

FIG. 10 shows a block diagram of a second device or a host device, inaccordance with an embodiment of the present disclosure. The seconddevice comprises of at least one analog to digital convertor (ADC) 409,at least one processor 410, at least one display unit 1002, at least oneuser input unit 1001, memory or storage unit 1002 and at least one modem411. The ADC 409 of the second devices such as, but not limited to,smartphones, tablets, personal computers, PDAs and any other computingdevice provide 48, 96, or 192 kHz sampling with 24 bits/sampleresolution. The audio bandwidth commonly used is in the range of is 50Hz to 18 kHz. As shown in FIG. 1, the AC coupling due to capacitor Cdoes not affect audio performance, as there is negligible information infrequencies below 50 Hz. Consequently, the AC coupling in the seconddevice will not affect the performance of the first device orsmartcable, since the center frequencies of VCOs for all the sensors arechosen to be much higher than 50 Hz. Human auditory system has up to 120dB dynamic range and most consumer audio solutions have 90+ dB dynamicrange. This is supported by 24 bits/sample in many Host devices. Thedynamic range provided by 24 bits/sample is more than adequate fordigitizing the composite FM signal from the smartcable.

FIG. 11 shows a signal processing module of the second device side, inaccordance with an embodiment of the present disclosure. The signalprocessing module comprises a bandpass filter, one or more FMdemodulation blocks and one or more feature extraction blocks. Thebandpass filter performs band-pass filtering of the composite FM signalto extract one or more FM streams. A Finite Impulse Response (FIR)filter has phase linearity properties and is ideal to perform thebandpass filtering of single sensor information. The bandpass filtereffectively separates each FM modulated signal from the compositediscrete signal received from the ADC. The FM demodulation moduletranslates each discrete sensor stream to a base band stream. The FMdemodulation is performed using the techniques such as, but not limitedto Hilbert Filter approach, Phase Locked Loop, and other FM demodulationtechniques. The processing module then extracts signal features such as,but not limited to ECG fiduciary points (PQRST), average heart rate(HR), instantaneous heart rate (IHR), and pNN50 or heart ratevariability; EEG features, motion features corresponding to physicalactivity; spirometer features corresponding to pulmonary function, SpO2for oxygen saturation, blood pressure features, body temperature, etc.

One embodiment of the present disclosure is a Display and StorageModule, in accordance with an embodiment of the present disclosure. TheDisplay and Storage Module control the display unit and storage of datafor post-processing and communication. The display unit provides atleast one of user input unit and Graphical User Interface (GUI) with atouch screen interface on host device, as shown in FIG. 10. The hostdevice provides user input unit to configure smart accessories andreceive signals from smart accessories. The GUI also provides for touchscreen and mouse control for manipulating the display of raw signals andextracted features on host device such as, but not limited to,smartphones, tablets, Laptops and personal devices. The storage unitstores the sensor signals and processed data for post processing,including comparison with previous recordings for trend analysis,comparison with cohorts for statistical analysis, etc.

In one embodiment of the present disclosure, the communication moduletransmits the sensor raw signals and the extracted features to a thirddevice such as another computer or a database server in the Internet.The communication module may also perform additional functions such asposting appropriate data to Electronic Medical Records (EMR) and/orsending alerts to the second device when certain signal features exceedpre-programmed thresholds.

One embodiment of the present disclosure is a third device comprising atleast one control unit, at least one modem, and at least one GraphicalUser Interface unit. The at least one control unit is configured toreceive at least one composite digital signal and perform at least oneof band pass filtering, demodulation and extracting at least one rawsignal sensed by a first device. The third device further comprises oneor more band pass filters to perform band pass filtering. In oneembodiment, each of the one or more band pass filters may have equalbandwidths. In another embodiment, the at least one of the one or moreband pass filters have a different bandwidth compared to at least oneanother band pass filter.

The at least one control unit of the third device is configured toreceive one or more threshold values and compare the extracted one ormore extracted features of the at least one raw signal against the oneor more threshold values. The demodulation performed by the at least onecontrol unit is one of frequency demodulation, amplitude demodulationand phase demodulation. The at least one Graphical User Interface unitof the third device is configured to receive one or more input commandsand display information associated with the demodulation.

In one embodiment, the third device is configured to generate an alarmwhen the at least one extracted feature is greater than an upperthreshold value or less than a lower threshold value, wherein the upperand the lower threshold values are associated with at least one ofelectrocardiogram (ECG), Electroencephalography (EEG), motion, airflowof respiratory system, body temperature, arterial oxygen saturationlevel, blood pressure and any other physiology signal.

As used herein, the term “determining” encompasses a wide variety ofactions. For example, “determining” may include calculating, computing,processing, deriving, investigating, looking up (e.g., looking up in atable, a database or another data structure), ascertaining and the like.Also, “determining” may include receiving (e.g., receiving information),accessing (e.g., accessing data in a memory) and the like. Also,“determining” may include resolving, selecting, choosing, establishingand the like.

As used herein, a phrase referring to “at least one of” a list of itemsrefers to any combination of those items, including single members. Asan example, “at least one of: a, b, or c” is intended to cover: a, b, c,a-b, a-c, b-c, and a-b-c.

The various illustrative logical blocks, modules and circuits describedin connection with the present disclosure may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array signal (FPGA) or other programmable logic device(PLD), discrete gate or transistor logic, discrete hardware componentsincluding operational amplifiers, instrumentation amplifiers or anycombination thereof designed to perform the functions described herein.A general purpose processor may be a microprocessor, but in thealternative, the processor may be any commercially available processor,controller, microcontroller or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isspecified, the order and/or use of specific steps and/or actions may bemodified without departing from the scope of the claims.

The functions described may be implemented in hardware, software,firmware, or any combination thereof. If implemented in software, thefunctions may be stored or transmitted over as one or more instructionsor code on a computer-readable medium. Computer-readable media includeboth computer storage media and communication media including any mediumthat facilitates transfer of a computer program from one place toanother. A storage medium may be any available medium that can beaccessed by a computer. By way of example, and not limitation, suchcomputer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer. Also, any connection is properly termed acomputer-readable medium. For example, if the software is transmittedfrom a website, server, or other remote source using a coaxial cable,fiber optic cable, twisted pair, digital subscriber line (DSL), orwireless technologies such as infrared (IR), radio, and microwave, thenthe coaxial cable, fiber optic cable, twisted pair, DSL, or wirelesstechnologies such as infrared, radio, and microwave are included in thedefinition of medium. Disk and disc, as used herein, include compactdisc (CD), laser disc, optical disc, digital versatile disc (DVD),floppy disk, and Bluray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers. Thus, insome aspects computer-readable media may comprise non-transitorycomputer-readable media (e.g., tangible media). In addition, for otheraspects computer-readable media may comprise transitorycomputer-readable media (e.g., a signal). Combinations of the aboveshould also be included within the scope of computer-readable media.

Thus, certain aspects may comprise a computer program product forperforming the operations presented herein. For example, such a computerprogram product may comprise a computer readable medium havinginstructions stored (and/or encoded) thereon, the instructions beingexecutable by one or more processors to perform the operations describedherein. For certain aspects, the computer program product may includepackaging material.

Software or instructions may also be transmitted over a transmissionmedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition oftransmission medium.

Further, it should be appreciated that modules and/or other appropriatemeans for performing the methods and techniques described herein can bedownloaded and/or otherwise obtained by a user terminal and/or basestation as applicable. For example, such a device can be coupled to aserver to facilitate the transfer of means for performing the methodsdescribed herein. Alternatively, various methods described herein can beprovided via storage means (e.g., RAM, ROM, a physical storage mediumsuch as a compact disc (CD) or floppy disk, USB storage devices, etc.),such that a user terminal and/or base station can obtain the variousmethods upon coupling or providing the storage means to the device.Moreover, any other suitable technique for providing the methods andtechniques described herein to a device can be utilized.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the methods and apparatus described above without departingfrom the scope of the claims.

The teachings herein may be incorporated into (e.g., implemented withinor performed by) a variety of apparatuses (e.g., devices). For example,one or more aspects taught herein may be incorporated into a phone(e.g., a cellular phone), a personal data assistant (“PDA”), asmartphone, an entertainment device (e.g., a portable media device,including music and video players), a headset (e.g., headphones, anearpiece, etc.), a microphone, a medical sensing device (e.g., abiometric sensor, a heart rate monitor, a pedometer, an ECG device, asmart bandage, etc.), a user I/O device (e.g., a watch, a remotecontrol, a light switch, a keyboard, a mouse, etc.), an environmentsensing device (e.g., a tire pressure monitor), a monitoring device thatmay receive data from the medical or environment sensing device (e.g., adesktop, a mobile computer, etc.), a point-of-care device, a hearingaid, a set-top box, or any other suitable device. The monitoring devicemay also have access to data from different sensing devices viaconnection with a network.

In some aspects a wireless device may comprise an access device (e.g.,an access point) for a communication system. Such an access device mayprovide, for example, connectivity to another network (e.g., a wide areanetwork such as the Internet or a cellular network) via a wired orwireless communication link. Accordingly, the access device may enableanother device (e.g., a wireless station) to access the other network orsome other functionality. In addition, it should be appreciated that oneor both of the devices may be portable or, in some cases, relativelynon-portable. Also, it should be appreciated that a wireless device alsomay be capable of transmitting and/or receiving information in anon-wireless manner (e.g., via a wired connection) via an appropriatecommunication interface.

The specification has described a method and a system for providing realtime remote guidance by an expert to a novice user to accomplish a task.The illustrated steps are set out to explain the exemplary embodimentsshown, and it should be anticipated that ongoing technologicaldevelopment will change the manner in which particular functions areperformed. These examples are presented herein for purposes ofillustration, and not limitation. Further, the boundaries of thefunctional building blocks have been arbitrarily defined herein for theconvenience of the description. Alternative boundaries can be defined solong as the specified functions and relationships thereof areappropriately performed. Alternatives (including equivalents,extensions, variations, deviations, etc., of those described herein)will be apparent to persons skilled in the relevant art(s) based on theteachings contained herein. Such alternatives fall within the scope andspirit of the disclosed embodiments. Also, the words “comprising,”“having,” “containing,” and “including,” and other similar forms areintended to be equivalent in meaning and be open ended in that an itemor items following any one of these words is not meant to be anexhaustive listing of such item or items, or meant to be limited to onlythe listed item or items. It must also be noted that as used herein andin the appended claims, the singular forms “a,” “an,” and “the” includeplural references unless the context clearly dictates otherwise.

It is intended that the disclosure and examples be considered asexemplary only, with a true scope and spirit of disclosed embodimentsbeing indicated by the following claims.

The present disclosure is not to be limited in terms of the particularembodiments described in this application, which are intended asillustrations of various aspects. Many modifications and variations canbe made without departing from its spirit and scope, as will be apparentto those skilled in the art. Functionally equivalent methods and deviceswithin the scope of the disclosure, in addition to those enumeratedherein, will be apparent to those skilled in the art from the foregoingdescriptions. Such modifications and variations are intended to fallwithin the scope of the appended claims. The present disclosure is to belimited only by the terms of the appended claims, along with the fullscope of equivalents to which such claims are entitled. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations may be expressly set forth herein for sakeof clarity.

In addition, where features or aspects of the disclosure are describedin terms of Markush groups, those skilled in the art will recognize thatthe disclosure is also thereby described in terms of any individualmember or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

What is claimed is:
 1. A first device with at least one instrumentationblock and a jack connectable to a second device with a socket and atleast one sensor, the first device comprising: at least one amplifier inthe instrumentation block configured to amplify at least one signalreceived from the at least one sensor; and one or more modulators in theinstrumentation block, wherein one or more modulators are configured tomodulate at least one amplified signal; wherein at least one modulatedsignal is transmitted to the second device upon connecting the jack tothe socket.
 2. The first device as claimed in claim 1 is configured toreceive power from the second device upon connecting the jack to thesocket.
 3. The first device as claimed in claim 1, wherein the at leastone signal is one of electrocardiogram (ECG), Electroencephalography(EEG), motion, airflow of respiratory system, body temperature, lightintensity of arterial oxygen saturation level, blood pressure and anyother physiology signal.
 4. The first device as claimed in claim 1further comprises a power source configured to supply power to the firstdevice.
 5. The first device as claimed in claim 1 optionally comprisesone or more instrumentation blocks, wherein each of the one or moreinstrumentation blocks is connectable to the at least one sensor.
 6. Thefirst device as claimed in claim 1, wherein each of the one or moremodulators is configured to operate with a unique modulation frequency.7. The first device as claimed in claim 1, wherein all the one or moremodulators have equal bandwidths.
 8. The first device as claimed inclaim 1, wherein at least one modulator has a different bandwidthcompared to at least one other modulator.
 9. The first device as claimedin claim 1, wherein the at least one modulators is configured to performone of frequency modulation, amplitude modulation and phase modulation.10. A second device with at least one ADC, at least one control unit, atleast one modem and at least one socket connectable to a first devicewith at least one instrumentation block and a jack, the second devicecomprising: the ADC configured to receive a composite analog signal fromthe first device through the at least one socket upon connecting to thejack and convert the analog signal in to a digital signal; and thecontrol unit configured to receive the digital signal and perform bandpass filtering, demodulation and extracting at least one raw signalsensed by the first device.
 11. The second device as claimed in claim 10is configured to provide power to the first device upon connecting tothe socket.
 12. The second device as claimed in claim 10 furthercomprises one or more band pass filters to perform band pass filtering,wherein all the band pass filters have equal bandwidths.
 13. The seconddevice as claimed in claim 10, wherein the at least one band pass filterhas a different bandwidth from at least one another band pass filterbandwidth.
 14. The second device as claimed in claim 10, wherein thedemodulation is one of frequency demodulation, amplitude demodulationand phase demodulation.
 15. The second device as claimed in claim 10further comprising at least one Graphical User Interface unit configuredto receive one or more input commands and display information associatedwith the demodulated signal.
 16. The second device as claimed in claim15, wherein the extracted features of the raw signals are displayed onthe at least one Graphical User Interface.
 17. The second device asclaimed in claim 10, wherein the at least one modem is configured totransmit at least one sample of the at least one raw signal to a thirddevice.
 18. The second device as claimed in claim 10, wherein the atleast one control unit is further configured to transmit at least onefeature from the at least one raw signal to a third device.
 19. Thesecond device as claimed in claim 10, wherein the at least one modem isfurther configured to transmit the extracted features of the rawsignals.
 20. The second device as claimed in claim 10, wherein thecontrol unit is further configured to receive one or more thresholds andcompare the extracted one or more extracted features against the atleast one threshold value.
 21. The second device as claimed in claim 10is configured to generate an alarm when the at least one extractedfeature is greater than the upper threshold value or less than a lowerthreshold value, wherein the said threshold values are associated withat least one of electrocardiogram (ECG), Electroencephalography (EEG),motion, airflow of respiratory system, body temperature, arterial oxygensaturation level, blood pressure and any other physiology signal.
 22. Afirst device with at least one sensor, at least one actuator, aninstrumentation block and a jack connectable to a second device with asocket, the first device comprising: at least one amplifier in theinstrumentation block configured to amplify at least one signal receivedfrom at the least one sensor; and at least one driver unit in theinstrumentation block to actuate at least one actuator, wherein the atleast one driver receives a driver signal from the second device uponconnecting the jack to the socket; wherein at least one signal sensed bythe at least one sensor is transmitted to the second device uponconnecting the jack to the socket.
 23. The first device as claimed in22, wherein the at least one sensor is a photodiode.
 24. The firstdevice as claimed in 22, wherein the at least one actuator is a LED. 25.The first device as claimed in claim 22 is configured to receive powerfrom the second device upon connecting the jack to the socket.
 26. Thefirst device as claimed in claim 22, wherein the at least one signal islight intensity changes induced by changes in arterial oxygen saturationlevels.
 27. The first device as claimed in claim 22 further comprises apower source configured to power the instrumentation block.
 28. A seconddevice with at least one ADC, at least one DAC, at least one controlunit, at least one modem and at least one socket connectable to a firstdevice with at least one instrumentation block and a jack, the seconddevice comprising: the at least one ADC configured to receive an analogsignal from the first device through the at least one socket uponconnecting to the jack and convert the analog signal in to a digitalsignal; and the at least one control unit is configured to: provide atleast one actuation signal to the at least one DAC; receive at least onedigital signal from the at least one ADC; and process the at least onedigital signal received from the at least one ADC; wherein at least onedrive signal is transmitted from the at least one DAC to the firstdevice upon connecting the at least one socket to the jack;
 29. Thesecond device as claimed in 28, wherein the at least one control unit isfurther configured to perform extracting at least one raw signal fromthe at least one digital signal and estimate arterial oxygen saturationfrom the at least one extracted raw signal.
 30. The second device asclaimed in claim 28 further comprises at least one modem configured totransmit the estimated arterial oxygen saturation to a third device. 31.The second device as claimed in claim 28 further comprises a displayinterface unit configured to display at least one of the extracted rawsignal and the estimated arterial oxygen saturation.
 32. The seconddevice as claimed in claim 28, wherein the at least one control unit isconfigured to process at least one digital signal synchronously with theat least one actuation signal.
 33. A method for processing at least onesignal being sensed by at least one sensor using a first device, themethod comprising: receiving the at least one signal being sensed by theat least one sensor, amplifying the received at least one signal;performing a predefined modulation on the amplified at least one signal;and transmitting the composite signal with at least one modulated signalto a second device through a jack of the first device, upon connectingthe jack to at least one socket of the second device.
 34. The method asclaimed in claim 33, wherein the at least signal is one ofelectrocardiogram (ECG) signals, Electroencephalography (EEG), motion,airflow of respiratory system, body temperature, light intensity changescaused by arterial oxygen saturation levels, blood pressure and anyother physiology signal.
 35. The method as claimed in claim 33, whereinthe predefined modulation is one of frequency modulation, amplitudemodulation and phase modulation.
 36. A system to acquire and process acomposite signal comprising at least one signal from at least onesensor, the system comprising: a first device with at least oneinstrumentation block and a jack connectable to a second device with asocket and the at least one sensor, the first device comprising: atleast one amplifier in the instrumentation block configured to amplifyat least one signal received from the at least one sensor; and one ormore modulators in the instrumentation block, wherein each of the one ormore modulators configured to modulate at least one amplified signal,the composite signal with at least one modulated amplified signal istransmitted to the second device upon connecting the jack to the socketand a second device with at least one ADC, at least one control unit, atleast one modem and at least one socket connectable to the first device,the second device comprising: the ADC configured to receive a compositesignal with at least one modulated amplified signal from the firstdevice through the at least one socket upon connecting to the jack andconvert the modulated amplified signal in to a digital signal; and thecontrol unit configured to receive the digital signal and perform bandpass filtering, demodulation and extracting at least one raw signalsensed by the at least one sensor.
 37. The system as claimed in claim36, wherein the at least one signal is one of electrocardiogram (ECG)signals, Electroencephalography (EEG), motion, airflow of respiratorysystem, body temperature, light intensity changes caused by arterialoxygen saturation levels, blood pressure and any other physiologysignals.
 38. The system as claimed in claim 36, wherein the first deviceis configured to receive power from the second device upon connectingthe jack to the socket.
 39. The system as claimed in claim 36, whereinthe first device further comprises a power source configured to powerthe instrumentation block.
 40. The system as claimed in claim 36,wherein the one or more modulators is configured to perform one offrequency modulation, amplitude modulation and phase modulation.
 41. Thesystem as claimed in claim 36, wherein the second device furthercomprises one or more band pass filters to perform band pass filteringand all the one or more band pass filters are configured with equalbandwidths.
 42. The system as claimed in claim 41, wherein at least oneband pass filter has a different bandwidth compared to at least oneother band pass filter.
 43. The system as claimed in claim 36, whereinthe demodulation is one of frequency demodulation, amplitudedemodulation and phase demodulation.
 44. The system as claimed in claim36, wherein the second device further comprising at least one displayinterface unit configured to receive one or more input commands anddisplay information associated with the at least one signal sensed bythe at least one sensor.
 45. A method for processing sensor signalscomprising: receiving one or more signals sensed by one or more sensors;amplifying the received one or more sensed signals; performing apredefined modulation on the one or more amplified signals; combiningthe one or more modulated signals to form a composite analog signal; andtransmitting the composite signal to a second device for furtherprocessing.
 46. A method for acquiring and processing a composite signalon a second device, the method comprising: receiving a composite signal;separating one or more signals from the composite signal; demodulatingthe separated one or more signals to base band; extracting one or morefeatures from the base band signal; communicating the one or more baseband signals and the extracted features to a third device.
 47. A seconddevice with at least one ADC, at least one control unit, at least onemodem and at least one socket connectable to a first device with atleast one instrumentation block and a jack, the second devicecomprising: the at least one ADC configured to receive an analog signalfrom the first device through the at least one socket upon connecting tothe jack and convert the composite analog signal in to a digital signal;and the at least one control unit configured to receive the compositedigital signal and transmit over the modem to a third device.
 48. Athird device with at least one control unit, at least one modem, and atleast one Graphical User Interface unit: the at least one control unitconfigured to receive at least one composite digital signal and performat least one of band pass filtering, demodulation and extracting atleast one raw signal sensed by a first device.
 49. The third device asclaimed in claim 48 further comprises one or more band pass filters toperform band pass filtering, wherein each of the one or more band passfilters have equal bandwidths.
 50. The third device as claimed in claim49, wherein the at least one of the one or more band pass filters has adifferent bandwidth compared to at least one another band pass filter.51. The third device as claimed in claim 48, wherein the demodulation isone of frequency demodulation, amplitude demodulation and phasedemodulation.
 52. The third device as claimed in claim 48, wherein theat least one Graphical User Interface unit is configured to receive oneor more input commands and display information associated with thedemodulation.
 53. The third device as claimed in claim 48, wherein theat least one control unit is configured to receive one or more thresholdvalues and compare the extracted one or more extracted features of theat least one raw signal against the one or more threshold values. 54.The third device as claimed in claim 48 is configured to generate analarm when the at least one extracted feature is greater than an upperthreshold value or less than a lower threshold value, wherein the upperand the lower threshold values are associated with at least one ofelectrocardiogram (ECG), Electroencephalography (EEG), motion, airflowof respiratory system, body temperature, arterial oxygen saturationlevel, blood pressure and any other physiology signal.